Apparatus and method for a helically perforated wound duct

ABSTRACT

The first roller dies will perforate, puncture the metal strip after the strip goes through the front guide. After the perforation the metal strip can then be corrugated. This is an improvement over punching the metal strip. Punching the metal, rotary punch, requires and extra step and leaves metal scrap, which is why punching metal for the first rolls would clog the machine and cause damage to the machine. The results of these tiny holes in the cylindrical duct help muffle the vibration and other noises from the motorized fan down the ductwork. The cylindrical perforated duct acts like a muffler. Air conditioning, bathroom exhaust fans, kitchen exhaust fans noise can me great reduced cheaply and efficiently. This perforated duct will be used with a vapor barrier and/or insulation.

BACKGROUND OF INVENTION Field of the Invention

This invention relates to ducts and more particularly to helically wound duct for supplying conditioned air and ventilation of air distribution

Description of the Related Art

HVAC (Heating Ventilation and Air Conditioning) systems use a series of duct to deliver and remove air from conditioned spaces. Fabricated ducts are most commonly fabricated with galvanized mild steel. Flexible ducting generally utilizes flexible plastic material over a metal helical coil to make round duct.

The accumulation of water, dirt and debris in ducts may result in periodic duct cleaning for mold growth in duct systems creates potential health hazards to structure occupants. Preventing mold growth and moisture is a by-product of HVAC systems, facilitating effective moisture removal to minimize mold growth. Other attempts to control mold growth include air filtration systems and installation of ultraviolet lights mounted in the system act as a mold air purifier. Construction of various HVAC components from copper and its alloys has shown to be an effective means to prevent mold growth on these components. The antimicrobial properties of copper have long been understood and accepted. In 2008 the EPA classified copper as antimicrobial. The growth of mold within ductwork of HVAC systems remains an unsolved problem.

HVAC systems use motorized fans to force air through the ducts. These fans make noise that occupants don't like to hear. Reducing noises from air conditioners, bathroom fans, and kitchen range fans is difficult without reducing air flow is well known to those skilled in the art.

Attempts have been made to reduce noise by reducing the air flow. Others have used round holes in plastic injected molded fan parts or used rotary punched holes for metal duct. Rotary punched holes include an extra step in metal duct construction and produce waste material.

There have been many in the prior art who have attempted to solve these problems with varying degrees of success. None, however have completely satisfied the requirements for a complete solution to the aforementioned problem. The following U.S. patents are attempts of the prior art to solve this problem.

U.S. Pat. No. 3,734,171 to Ares, et al. discloses a cartridge-type heat exchange coil installed in a conventional air duct by way of a single side opening in the duct wall so that the coil rigidly positions itself within the duct cavity. The coil preferably has certain arms extending from its ends to provide duct-side piercing, positioning, and suspensioning. The arms are disposed outside the duct when the coil is installed, such that wires or straps can be attached to the arms to suspend the coil without appreciably loading or stressing the duct.

U.S. Pat. No. 4,058,996 to Schaefer, et al. discloses a machine for manufacturing metal duct or pipe having improved efficiency, reliability, and speed of operation. A continuous, thin metal strip is corrugated, helically would and seamed to form a durable yet bendable duct or pipe. The corrugation of the strip along its longitudinal axis is achieved by passing the thin metal strip through a plurality of synchronously driven (same RPM) corrugating strip roller die stands, each stand having progressively larger diameter rollers such that as a point on the metal ship passes from one corrugating strip roller stand to the next, the next stand rollers have progressively higher circumferential surface speed that the last, creating a pull on the strip material emerging from the preceding roller stand, the pulling force at each stand preventing wrinkling or buckling of the strip as it passes through the corrugating operation. The corrugated strip is then helically wound into a bendable duct having a circular cross section by passing adjacent edges of the strip through the novel, nonfouling front and rear strip lock tucking fingers which act to quickly but reliably interlock adjacent strip edges. The interlocked seam is then passed through and between compression rollers which have, peripherally disposed, a modified gear tooth pattern about their circumference forming a plurality of ridges and furrows along the seam. The bottom compression rollers is ball-bearing mounted for free and unrestrictive rotation. All of the machine roller, including the strip corrugating die rollers and the compression seam forming rollers are synchronously driven in rotation by a common drive motor a through an endless drive chain. The continuously formed metal pipe may be cut to any desired length through the use of a cam-actuated movable cut-off saw blade which severs the finished pipe perpendicular to the longitudinal axis of the pipe.

U.S. Pat. No. 5,325,893 to Takagi, et al. discloses an air duct which includes a tubular member formed from a metal sheet. A paper is disposed around an outer periphery of the tubular member for preventing condensation droplets: condensed on the tubular member from dripping, and an adhesive is interposed between the tubular member and the paper to adhesively secure the tubular member and the paper. Furthermore, a paper for an air duct, adapted to be secured to an outer periphery of the air duct, is disclosed. The paper is produced from a material including a papermaking pulp and is characterized by the following: a wet strength of at least 0.3 kgf/15 mm, a critical value for dipping of water droplets of at least 45 g/m.sup.2, and a basis weight of 40 to 5000 g/m.sup.2.

U.S. Pat. No. 5,520,854 to Proco, et al. discloses an apparatus and method for inhibiting the accumulation of bacteria within a humidifier including a primary water path for directing water directly from a water source to a humidifier during its operation. When the humidifier is shut-down for a cleaning operation, water is directed through a bacteria-removing device before entering the humidifier. Water contact surfaces within the humidifier are preferably lined with copper to further inhibit bacterial growth.

U.S. Pat. No. 5,931,0002 to Nagashima discloses an air cooling duct and a cooling apparatus which can effect ventilation and cooling with certainty while suppressing noise. The cooling air duct is provided on a wall of a housing, in which a heat source is accommodated, and inducts external air into the housing or vents air in the housing to the outside of the housing in order to cool the inside of the housing. The cooling air duct defines an air path for communicating the inside and outside of the housing with each other and further defines an expansion chamber formed on the air path. The cooling apparatus includes the cooling air duct. The cooling air duct and the cooling apparatus can be used principally to cool the inside of a housing of an electronic apparatus such as a computer or a communication apparatus.

U.S. Pat. No. 6,123,616 to Otsuka discloses an pipe-like air duct formed of hard aluminum foil. Concaves and convexes give flexibility to the air duct, kraft paper is wound on both surfaces of the aluminum foil. This air duct is disposed between an outer panel and an inner panel of vehicle body along the panels, laid to the rear seat of the vehicle, the air duct is subjected to plastic deformation, by which the shock energy caused by an external force is absorbed.

United States Patent 2004/0120845 to Potcmber, et al. discloses a method and apparatus for neutralizing airborne pathogens in ventilated air, and in heating or air conditioning systems. The pathogen neutralization system is effective against a wide spectrum of pathogens, it incorporates commercially available components, and it can be readily integrated into commercial HVAC systems where it neutralizes airborne pathogens in large volumes of ventilated air in real time without an chemical reagents. Typically the system has a flow-through reaction chamber that contains a UV light source that emits short intense flashes of broad-spectrum UV light, a source of water vapor or spray, and an ozone generator. The system generates highly reactive ozone intermediates by irradiating ozone gas with UV light in the presence of water droplets of water vapor. The pathogens that can be neutralized by this system include bacteria, viruses, spores, fungi and parasites.

The United States Patent 2007/0217944 to Potember, et al. discloses a method and apparatus for neutralizing the airborne pathogens and chemical toxins in ventilated air, and in heating or air conditioning systems. The pathogen-chemical toxin neutralization system is effective against a wide spectrum of pathogens and toxins, it incorporates commercially available components, and it can be readily integrated into commercial HVAC systems where it decontaminates large volumes of ventilated air in real time without any chemical reagents. The system has a flow-through reaction chamber that contains a UV light source that emits short intense flashes of broad-spectrum UV light, a source aqueous hydrogen peroxide that can be a reservoir or a hydrogen peroxide generator, and optionally a source of ozone. The interaction of UV light and hydrogen peroxide generates hydroxyl radicals that neutralize pathogens and chemical toxins as they pass through the reaction chamber in real time. The pathogens that can be neutralized by this system include bacteria, viruses, spores, fungi and parasites.

Although the aforementioned prior art have contributed to the development of the art of mold and mildew control in ducts, none of these prior patents have solved the needs of this art.

Therefore, it is an object of this invention to provide an improved apparatus for HVAC duct systems.

Another object of the present invention to provide an improved apparatus for the prevention of mold and mildew growth in HVAC ducts, and ventilation ducts.

Another object of this invention is to provide an improved apparatus that is easy to cost and effectively produce.

Another object of the present invention is to provide an improved apparatus for the muffling of motorized fan noises in HVAC duct and other ventilation ducts.

The foregoing has outlined some of the more pertinent objects of the present invention. These objects should be construed as being merely illustrative of some of the more prominent features and applications of the invention. Many other beneficial results can be obtained by applying the disclosed invention in a different manner or modifying the invention within the scope of the invention. Accordingly other objects in a full understanding of the invention may be had by referring to the summary of the invention and the detailed description describing the preferred embodiment of the invention.

SUMMARY OF THE INVENTION

A specified embodiment of the present invention is shown in the attached drawings. For the purpose of the summarizing the invention, the invention relates to an improved apparatus for producing a helically wound duct from a strip. The strip is made from copper, zinc, for antimicrobial purposes, or aluminum or steel. The apparatus comprises and elongated strip frame coupled to an elongated frame. A front guide is coupled to the elongated strip frame for adjusting the tracking of the strip. The first set of roller dies will perforate, puncture the metal strip. These small holes are made before corrugating the strip. A plurality of a pair of corrugated roller dies are coupled to the elongated strip for progressively corrugating the strip. A finishing pair of corrugated roller is coupled to the elongated strip frame fix creating a primary ascending leg in the primary edge of the strip and a secondary descending leg in the secondary edge of the strip. A strip guide is coupled to the elongated strip frame for adjusting the tracking of the strip. A plurality of a helically disposed roller are coupled to the elongated strip frame for creating a helically wound strip. A jointer guide is coupled to the elongated strip frame having a guide body. A guide shoulder extends from the interior surface of the guide body. A guide arm is coupled to the guide shoulder fix defining a guide channel between the interior surface of the guide body and the guide arm. The guide arm has an exterior surface, an interior surface, a bottom surface and a top surface. The exterior surface of the guide arm define a primary leg guide surface. The primary leg guide surface maintains contact with the primary ascending leg of the strip for defining a primary alignment tool. The external surface of the guide arm has a recessed secondary leg guide surface. The recessed secondary leg guide surface maintains contact with the secondary descending leg of the strip for defining a secondary alignment tool. A front tucker has a radius finger to progressively bending the primary edge and the secondary edge of the strip. A rear tucker has a tapered edge for converging the primary edge and the secondary edge of the strip into the radius finger. The primary alignment tool and the secondary alignment tool assist in aligning the primary ascending leg and the secondary leg of the strip before entering the front tucker and the rear tucker. A pair of knurl corrugated roller dies compressing and knurling the primary edge with the secondary edge of the strip for defining a continuous helically seam. The helically wound strip and the continuous helically seam define a cylindrical duct. A saw device is coupled to the elongated duct frame for cutting the cylindrical duct to length.

The invention is also incorporated in the method of producing a helically wound duct comprising the steps of positioning a metal strip through a flattening role. The tracking of the strip is adjusted with a rear guide. The metal strip is inserted into a squeegee roller for removing excess fluid from the metal strip. The tracking of the strip is adjusted with the front guide. The strip is perforated, punctured with the first set of roller dies, before corrugation begins. The strip is corrugated with a plurality of a pair of corrugated miler dies. A primary ascending leg in the primary edge of the strip and a secondary descending leg in the secondary edge of the strip are formed with a finishing pair of corrugated roller dies. The tracking of the strip is adjusted with a strip guide. A helically wound strip is formed with a plurality of helically disposed roller dies. An expansion corrugated roller is compressed against the plurality of the helically disposed roller dies for maintaining a consistent diameter for the cylindrical duct. The primary ascending leg of the strip is maintained against a primary leg guide surface. The secondary descending leg of the strip is maintained against a recessed secondary leg guide surface. The primary edge is bent and interlocked with the secondary edge of the strip with a front tucker and a rear tucker. The primary edge is compressed and knurled with the secondary edge of the strip with a pair of knurl corrugated roller dies. The helically wound duct is cut with a saw.

The foregoing has outlined rather broadly the more pertinent and important features of the present invention in order that the detailed description that follows may be better understood so the present contribution to the art can be more fully appreciated. Additional features of the invention will be described hereinafter which form the subject matter of the invention. It should be appreciated by those skilled in the art that the conception and the specific embodiments disclosed may be readily utilized as a basis for modifying or designing other structures for carry out the same purpose of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do no depart from the spirit and scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

For fuller understanding of the nature and objects of the invention, reference should be made to the following detailed description taken in connection with the accompanying drawings in which:

FIG. 1 is a top view of an apparatus for producing a helically wound duct incorporating the present invention;

FIG. 2 front view of the helically wound duct machine

FIG. 3 is a rear isometric view of a jointer guide and a guide mounting block

FIG. 4 is a front isometric view of FIG. 3

FIG. 5 is a top view of FIG. 3

FIG. 6 is a front view of FIG. 3

FIG. 7 is a left side view of FIG. 3

FIG. 8 is a right side view of FIG. 3

FIG. 9 is an exploded view of FIG. 3

FIG. 10 is an exploded view of FIG. 4

FIG. 11 is a view similar to FIG. 4 illustrating the guide mounting block securing the jointer guide to an elongated strip frame wherein the jointer guide has a first positioned relative to the guide mounting block;

FIG. 12 is a view similar to FIG. 11 illustrating the jointer guide having a second positioned relative to the guide mounting block for permitting various coupling positions for the jointer guide relative to the elongated strip frame;

FIG. 13 is an enlarged portion of FIG. 2

FIG. 14 is an enlarged portion of FIG. 1

FIG. 15 is a sectional view along line 15-15 in FIG. 13

FIG. 15A is an enlarged portion of the FIG. 5 illustrating a finishing pair of corrugated roller dies for creating a primary ascending leg in a primary edge of the strip and secondary descending leg in the secondary edge of the strip;

FIG. 16 is a sectional view along line 16-16 in FIG. 13

FIG. 16A is an enlarged portion of FIG. 16 illustrating a primary leg guide surface of the jointer guide maintaining contact with the primary ascending leg of the strip for defining a primary alignment tool;

FIG. 16B is an enlarged portion of FIG. 16A;

FIG. 17 is a sectional view along line 17-17 in FIG. 13

FIG. 17A is an enlarged portion of FIG. 17 illustrating the front view of the jointer guide in relation to the rear tucker and front tucker;

FIG. 17B is an opposite directional view of FIG. 17A illustrating the front view of the jointer guide in relation to the rear tucker and the front tucker;

FIG. 17C is an enlarged portion of FIG. 17A;

FIG. 17D is an enlarged portion of FIG. 17B illustrating a recessed secondary leg guide surface maintaining contact with the secondary descending leg of the strip for defining a secondary alignment tool;

FIG. 18 is a sectional view along line 18-18 in FIG. 13;

FIG. 18A is an enlarged portion of FIG. 18 illustrating both the primary alignment tool and the secondary alignment tool aligning the primary ascending leg and the secondary descending leg and maintaining the primary ascending leg and secondary descending leg in close proximity before the primary ascending leg and the secondary descending leg engage the front tucker and the rear tucker;

FIG. 18B is an enlarged portion of FIG. 18A illustrating the primary ascending leg and the secondary descending leg beginning engagement with the front tucker and the rear tucker;

FIG. 19 is a sectional view along line 19-19 in FIG. 13;

FIG. 19A is an enlarged portion of FIG. 19 illustrating the front tucker progressively bending the primary edge and the secondary edge of the strip and the rear tucker converging the primary edge and the secondary edge of the strip into the front tucker;

FIG. 19B is an enlarged portion of 19A

FIG. 20 is a sectional view along line 20-20 in FIG. 13;

FIG. 20A is an enlarged portion of FIG. 20 illustrating a pair of knurl corrugated roller dies compressing the knurling the primary edge with the secondary edge of the strip for defining a continuous helically seam;

FIG. 20B is an enlarged portion of FIG. 20A;

FIG. 21 is a sectional view along line 21-21 in FIG. 13;

FIG. 21A is an enlarged portion of FIG. 21 illustrating the completed compression and knurling of the primary edge with the secondary edge of the strip for defining a continuous helically seam;

FIG. 21B is an enlarged portion of FIG. 21A

FIG. 22 is a sectional view along line 22-22 in FIG. 13 illustrating an expansion corrugated roller compressing against one of the plurality of helically disposed roller dies for maintaining a consistent diameter for the cylindrical duct;

FIG. 23 is a front isometric view of a cylindrical duct with perforation having been corrugated into a cylindrical duct. The metal being copper, zinc, for their antimicrobial properties in fighting mold and mildew growth, or steel or aluminum;

FIG. 24 is a side view of FIG. 23;

FIG. 25 is a side view of FIG. 24;

FIG. 26 is a sectional view along line 26-26 in FIG. 25 illustrating the perforated holes and continuous helically seam includes that construct the helically wound duct that uses an interlocking seam;

FIG. 28 is a top view of the metal strip after the first rolls perforate, puncture, but before the corrugating the metal strip.

FIG. 29 is an isometric view of the first roller dies that cut, perforate the metal strip;

FIG. 30 is a front view of the pair of the first roller dies that cut, perforate the metal strip;

DETAILED DISCUSSION

FIGS. 1-22 are various view of an apparatus for producing a helically wound duct 10 as shown in FIGS. 23-26 from one metal elongated strip frame 30 coupled to an elongated duct frame 32. A front guide 40 is coupled to the elongated strip frame 30 for adjusting the tracking of the strip 20. The first roller dies puncture, perforate the metal strip FIGS. 29-30. The metal strip can be made of copper, zinc for their antimicrobial properties, or steel, aluminum. The small holes will help muffle the noise down the ductwork where the motorized fan makes noise. A plurality of pair of corrugated roller dies 42 are coupled to the elongated strip frame 30 or progressively corrugating the strip 20. A finishing pair of corrugated roller dies 44 is coupled to the elongated strip frame 30 or progressively corrugating the strip 20. A finishing pair of corrugated roller dies 44 is coupled to the elongated strip frame 30 for creating a primary ascending leg 50 in the primary edge 26 of the strip 20 a secondary descending leg 52 in the secondary edge 28 of the strip 20.

A strip guide 60 is coupled to the elongated strip frame 30 for adjusting the tracking of the strip 20. A plurality of helically disposed roller dies 62 are coupled to the elongated strip frame 30 for creating a helically wound strip 64. A jointer guide 70 is coupled to the elongated strip frame 30 having a guide body. A guide shoulder 86 extends from the interior surface 76 of the guide body 72.

A guide arm 88 is coupled to the guide shoulder 86 for defining a guide channel 90 between the interior surface 76 of the guide body 94, a bottom surface 96 and a top surface 98. The exterior surface 92 of the guide arm 88 defines a primary leg guide surface 100. The primary leg guide surface 100 maintains contact with the primary ascending leg 50 of the strip 20 for defining a primary alignment tool 102. The external surface 92 of the guide arm 88 has a recessed secondary leg guide surface 104. The recessed secondary leg guide surface 104 maintains contact with the secondary descending leg 52 of the strip 20 for defining a secondary alignment tool 106.

A front tucker 110 has a radius finger 112 for progressively bending the primary edge 26 and the secondary edge 28 of the strip 20. A rear tucker 120 has a tapered edge 122 for converging the primary edge 26 and the secondary edge 28 of the strip 20 into the radius finger 112. The primary alignment tool 102 and the secondary edge 28 of the strip 20 into the radius finger 112. The primary alignment tool 102 and the secondary alignment tool 106 assist in aligning the primary ascending leg 50 and the secondary descending leg 52 of the strip 20 before entering the front tucker 110 and the rear tucker 120.

A pair of knurl corrugated roller dies 130 compressing and knurling the primary edge 26 with the secondary edge 28 of the strip 20 fix defining a continuous helically seam 132. The helically wound strip 64 and the continuously helically seam 132 define a cylindrical duct 134. A saw device 140 is coupled to the elongated duct frame 32 for cutting the cylindrical duct 134 to length.

The top surface 98 of the guide arm 88 further includes a taper arm surface 150 for directing the secondary descending leg 52 into the recessed secondary leg guide surface 104. The top surface 84 of the guide body 72 includes a taper body surface 152 for directing the secondary descending leg 52 into the recessed secondary leg guide surface 104. The jointer guide 70 may be secured to the elongated strip frame by a guide mounting block 154.

An expansion corrugated roller 60 compresses against one of plurality of helically disposed roller dies 62 for maintaining a consistent diameter for the cylindrical duct 134. The expansion corrugated roller 60 may be secured within the plurality of the helically disposed roller dies 62 by a magnetic couple 162 having a support rod 164 between the expansion corrugated roller 60 and the magnetic coupler 162.

The subject invention farther includes a method fix producing a helically wound duct 10. The method comprises the steps of positioning a metal strip 220 through a flattening role 300. The tracking of the strip 20 is adjusted with a rear guide 302. After the metal strip is dipped in the dip tank the metal strip is adjusted with the front guide 40. The strip is punctured, perforated with the first set of roller dies FIG. 29-30. The strip 20 is corrugated with a plurality of pair of corrugated roller dies 42. A primary ascending leg 50 in the primary edge 26 of the strip 20 and the secondary descending leg 52 in the secondary edge 28 of the strip 20 are formed with a finishing pair of corrugated roller dies 44. The tracking of the strip 20 is adjusted with a strip guide 60 a helically wound strip 64 is formed with a plurality of helically disposed roller dies 62. An expansion corrugated roller 160 is compressed against one of the plurality of helically disposed roller dies 62 fix maintaining a consistent diameter for the cylindrical duct 134. The primary ascending leg 50 of the strip 20 is maintained against a primary leg guide surface 100. The secondary descending leg 52 of the strip 20 is maintained against a recessed secondary leg guide surface 104. The primary edge is bent and interlocked with the secondary edge of the strip with the front tucker and the rear tucker. The primary edge 26 is compressed and knurled with the secondary edge 28 of the strip 20 with a pair of knurl corrugated roller dies 130. The helically wound duct 134 is cut with a saw 140.

Although the invention has been described in its preferred form with a degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and the numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention. 

What is claimed is:
 1. An apparatus for producing a helically wound duct from a strip, the apparatus comprising: An elongated strip frame coupled to an elongated duct frame; A front guide coupled to said elongated strip frame for adjusting the tracking of the strip; A first position roller die to puncture, perforate the metal strip; A plurality of pair of corrugated roller dies coupled to said elongated strip frame for progressively corrugated the perforated strip; A finishing pair of corrugated roller dies couple to said elongated strip frame for creating a primary ascending leg in the primary edge of the strip and a secondary leg in the secondary edge of the strip; A strip guide couple to said elongated strip frame for adjusting the tracking of the strip; A plurality of helically disposed roller dies coupled to said elongated strip frame for creating a helically wound duct; A jointer guide couple to said elongated strip frame having a guide body extending between a exterior surface, an interior surface, a first side surface, a second side surface, a bottom surface and a top surface; guide shoulder extending from said interior surface of said guide body; A guide arm coupling to said guide shoulder for defining a guide channel between said interior surface of said guide body and said guide arm; Said exterior surface of said guide arm defining a primary leg guide surface Said primary leg guide surface maintains contact with the primary ascending leg the strip for defining primary alignment tool; Said external surface of said guide arm having a recessed secondary leg guide surface; Said recessed secondary leg guide surface maintains contact with the secondary descending leg of the strip for defining a secondary alignment tool; A front tucker having a radius finger for progressively bending the primary edge and the secondary edge of the strip; A rear tucker having a tapered edge for converging the primary edge and the secondary edge of the strip into said radius finger; Said primary alignment tool and said secondary alignment tool assist in aligning the primary ascending leg and the secondary descending leg of the strip before entering said front tucker and said rear tucker; A pair of knurl corrugated roller dies compressing and knurling said primary edge with the secondary edge of the strip for defining a continuous helically seam; Said helically wound strip and said continuously helically seam defining a cylindrical duct; A saw device coupled to said elongated duct frame for cutting said cylindrical duct to length
 2. An apparatus for producing helically wound duct from a strip as set for in claim 1, wherein said top surface of said guide arm further includes a taper arm surface for directing secondary descending leg into said recessed secondary leg guide surface; and said top surface of said guide body includes a taper body surface for directing the secondary descending leg into said recessed secondary leg guide surface.
 3. An apparatus fix producing a helically wound duct from a strip as set forth in claim 1 further including an expansion corrugated roller compressing against one of said plurality of helically disposed roller dies for maintaining a consistent diameter for said cylindrical duct.
 4. A method for producing a helically wound duct from a metal strip. The methods Comprising the steps of adjusting the tracking of the strip with a front guide; the first roller dies perforate, puncture small holes in the strip before corrugation. Corrugating the perforated strip with a plurality of pair of corrugated roller dies; forming a primary ascending leg in the primary edge of the strip and a secondary descending leg in the secondary edge of the strip with a finishing pair of corrugated roller dies; Adjusting the tracking of the strip with a strip guide; Forming a helically wound strip with a plurality of helically disposed roller dies; Maintaining the primary ascending leg of the strip against a primary leg guide surface; Maintaining the secondary descending leg of the strip against a recessed secondary leg guide surface; Bending and interlocking the primary edge with the secondary edge of the strip with the front tucker and a rear tucker; Compressing and knurling the primary edge with the secondary edge of the strip with a pair of knurl corrugated roller dies; and cutting the helically wound duct with a saw.
 5. A method for producing a helically wound duct, the methods comprising the steps of positioning a metal strip through a flattening roll; Adjusting the tracking of the strip with a read guide; Dipping the metal (copper, zinc both antimicrobial, or aluminum, steel) strip into the lubricating dip tank; Inserting the metal strip into a squeegee roller for removing excess fluid; Adjusting the tracking of the strip with a front guide; Using the first pair of roller dies that puncture, perforate the metal strip then corrugating the strip with polarity of pair of the corrugated roller dies; Forming a primary ascending leg in the primary edge of the strip and a secondary descending leg in the secondary edge of the strip with a finishing pair of corrugated roller dies; Adjusting the tracking of the strip with a strip guide; Forming a helically wound strip with a plurality of helically disposed roller dies; Compressing an expansion corrugated roller die against one of said plurality of helically disposed roller dies for maintaining a consistent diameter for said cylindrical duct; Maintaining the primary ascending leg of the strip against a primary leg guide surface; Maintaining the secondary descending leg of the strip against a recessed secondary leg guide surface; 